Testing device.



D. D. MILLER.

TESTING DEVICE.

APPLICATION FILED NOV. 11. 1916.

Patented Jan. 1, 1918..

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UNITED STATES PATENT OFFICE.

DANIEL D. MILLER, 01? NEW YORK, N. Y., ASSIGNOR TO WESTERN ELECTRIC COMPANY,

INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.-

TESTING DEVICE.

Specification of Letters Patent.

Application filed November 17, 1916. Serial No. 131,929.

To all whom it may concern:

Be it known that I, DANIEL D. MILLER, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Testing Devices, of which the following is a full, clear, concise, and exact description.

This invention relates to testing devices and more particularly to such devices for determining the contact pressure of relay contact springs.

The object of this invention is the production of an efiicient, compact and durable device of this character, composed of few parts.

This invention is illustrated in the accompanying drawings, wherein Figure 1 is a front elevation of the testing device; Fig. 2 is a perspective of the working parts of the device; and Fig. 3 is the cover.

Referring to the drawings, the test device consists of a base 5 having bent end portions 6 and 7 formed integrally therewith. To the lower end portion 7 is secured a block 8. A fiat steel spring 9 is secured to one side of the block and forms a resilient hinge for a finger 10 mounted upon the free end of the spring 9. The freeend of this finger 10 extends through an opening 11 in the upper end portion 6. A threaded rod 15 is rotatably fastened between the end portions 6 and 7. Encircling the lower end of the rod 15 is a spiral spring 16, the upper end of which is secured to a collar 17 having threaded engagement with the rod 15. The lower end of the spiral spring 16 is engaged by the bifurcated ends of an angle plate 18 attached to the lower end of the finger 10. The finger 10 and the angle plate 18 form a lever pivotally supported by the block 8 by means of the flexible hinge 9, and weighted or' tensioned at one end by means of the spiral spring 16. The tension of spring 16 normally holds the finger 10 (or longer arm of the lever) against the edge of the opening 11. By means of a knurled collar 20 fastened to the rod 15 and extending through an opening 21 in the base 5 and an opening 22 in cover plate 25, the position of the collar 17 may be varied and the tension of spiral spring 16 increased or decreased. By means of the a perspective ofconstruction shown in the drawing and hereinbefore described, an increase or decrease of tensionof the spiral spring 16 is transmitted to and causes a corresponding increase or decrease of tension on the finger 10. A pointer 26 carried by the collar 17 registers with a slot 27 in the base 5. As shown in Fig. 1, a scale is provided on the base adjacent the slot 27, so that the degree of tension on the free end of the finger 10 may be readily, easily and accurately varied between predetermined limits. Formed integrally with the cover plate 25 are bent side portions 28 and 29. A protecting bracket 35 is pivoted to the side portions 28 and 29 of the cover plate 25, so that when the testing device is not in use, the bracket 35 may be swung into the position shown in Fig. 1 to protect the end of the finger 10. The bracket 35 is provided with detents 31, 31 which are adapted to engage projections 32, 32 to lock the bracket in the position shown in Fig. 1. The detents 31, 31 are also adapted to engage projections 33, 33 to lock the bracket in its alternate position, as when the testing device is being used. The block 8 and a short rod 36 fastened to the base form spacing members for the cover and are threaded to receive screws for holding the cover in place.

The scale on the base 5 is preferably in grams. Suppose that it is desired to adjust the contact springs of a relay so that the minimum contact pressure therebetween shall be thirty grams, the indicator of the testing device is set to 30 on the scale, and the contact spring is then adjusted until the contact spring will remain stationary while the finger 10 moves, the end of the finger 10 being in engagement with the side of the contact-actuated spring at the free end thereof and acting against the pressure of the contact spring, thereby indicating that the contact pressure is greater than thirty grams.

What is claimed is:

1. .A testing device comprising a base, one end portion thereof bent at substantially right angles thereto and having an opening therein, a lever pivotally mounted on the base operative independently of the position of said base and having a long and a short arm, the long arm thereof projecting through such opening in such end portion, tensioning means attached to the short arm of the lever, and means for increasing or decreasing the tension of said means.

2. A testing device comprising a base plate, one end portion thereof bent at substantially right angles thereto and provided with an opening therein, a block secured to the base plate near the other end thereof, a lever flexibly mounted intermediate its ends upon the block operative independently of the position of said base and having the longer arm thereof extending along the length of the base plate through such open-- ing in such end portion and beyond the end of the base, a spring attached at the free end to the short arm of the lever, a stop on the base against which the longer arm of the lever is normally held by the tension of the spring, and means for increasing or decreasing the tension of the spring.

3. A testing device comprising a base having end portions bent at substantially right angles thereto, one of said portions having an opening therein, a block secured to the base near the other end thereof, a lever flexibly mounted intermediate its ends upon the block operative independently of the position of said base and having the longer arm thereof extending along the length of the base plate through said opening 1n the first mentioned end portion, a movable block, a

spiral spring connected at one end to the movable block and at the other end to the short arm of the lever, a stop on the base against which the longer arm of the lever is normally held by the tension of the spring, and means supported by the base for varying the position of the movable block to increase or decrease the tension on the lever.

4. A testing device comprising a base plate having end portions bent at substantially right angles thereto, a block secured to the base plate near one end thereof, one of said end portions having an opening therein, a lever flexibly mounted intermediate its ends upon the block and having the longer arm thereof extending along the length of the base plate through said openin in the first mentioned end portion, a movable block, a spiral spring connected at one end to the movable block and at the other end to the to for registering with end portions of the base plate to form an inclosure for the working parts.

5. A testing device comprising a base plate having longitudinal and transverse slots therein and having the end portions of said base plate bent at substantlally right angles thereto, one of said end portions having an aperture therein, a block secured to sald base near the other of said end ortions, a lever flexibly mounted intermediate its ends upon said block with the longer arm thereof extending along the length of said base through said aperture, a movable block, a spiral spring connecting at one end to said block and at the other end to the shorter arm of said lever for holding the longer arm of the lever against an edge of said aperture, a rotatable rod supported by said end portions of said base and having threaded engagement With said movable block, whereby the position of said block may be varied to vary the tension of the lever, a pointer carried by said block and traveling in said longitudinal slot for indicating the tension of said lever, a cover plate with a transverse slot and having slde portions bent at substantially right angles thereto for registering with said end portions of said base plate to form an inclosure for the working parts, a knurled collar secured to said rod and a portion of the edge thereof extending through each of said transverse slots in said base and cover plates for rotatin such rods, and a bracket pivoted to the send side portions of said cover plate for protecting the.

exposed end of the longer arm of said lever when not in use.

6. A testing device comprising an adjustable spring tensioned lever included in a casing, said casing provided with an aperture in one end thereof through which one end of said lever projects, and a movable bracket mounted on said casing adapted to be positioned to protect said end of said lever.

7. A testing device comprising an inclosing casing having an aperture in one end thereof, a pointed spring tensioned lever mounted within said casing and the point thereof projecting through said aperture, meansoperable externally of said casing for adjusting the tension of said spring, and a movable bracket attached to the exterior of said casing adapted to be positioned to protect said point of said lever.

In testimony whereof, I hereunto subscribe my name this 16th day of November DANIEL D. MILLER. 

